Topological light bullets supported by spatio-temporal gain

TL;DR

This paper demonstrates that specific spatio-temporal gain landscapes can stabilize three-dimensional light bullets, including vortex structures, by balancing diffraction, nonlinearity, absorption, and localized gain effects.

Contribution

It introduces the concept of using tailored gain landscapes to support and stabilize topological light bullets and vortex structures in three dimensions.

Findings

Stable fundamental light bullets supported by Gaussian gain landscapes.

Vortex bullets with topological phase dislocations supported by ring-like gain landscapes.

Suppression of instabilities and arrest of collapse in spatiotemporal wavepackets.

Abstract

We reveal that the competition between diffraction, cubic nonlinearity, two-photon absorption, and gain localized in both space and time results in arrest of collapse, suppression of azimuthal modula-tion instabilities for spatiotemporal wavepackets, and formation of stable three-dimensional light bul-lets. We show that Gaussian spatiotemporal gain landscapes support bright, fundamental light bullets, while gain landscapes featuring a ring-like spatial and a Gaussian temporal shapes may support stable vortex bullets carrying topological phase dislocations.